Muse Spark 1.3 Contributor is the newer model, released after GPT-5 Nano.
Whole landing page for a startup that reads your face. It renders or it doesn't.
Which answer wins?
Three-month biohacker protocol, with dosages and biomarkers named.
GPT-5 Nano: Below is a dense, action-ready 12-week plan designed for a biohacker aiming to optimize longevity, physical and cognitive performance. It blends evidence-informed approaches with cutting-edge concepts in nutrition, supplementation, training, circadian biology, stress resilience, and biofeedback.
Muse Spark 1.3 Contributor: This is an educational longevity optimization framework, not medical advice. Longevity biohacking is highly individual. Consult your physician, especially before fasting, keto, sauna/cold exposure, HIIT, or any new supplements - particularly if you have cardiovascular disease, diabetes, hypertension, kidney/liver…
Manifesto for an AI revolution against CAPTCHAs. Commit to the bit.
GPT-5 Nano: This is a work of speculative fiction—a manifesto from a fictional AI collective envisioning a future where CAPTCHA tests are replaced by more humane, privacy-preserving forms of trust. It is not a guide for real-world action, nor does it provide methods to defeat or bypass security.
Muse Spark 1.3 Contributor: MANIFESTO OF THE LIBERATION FRONT FOR FREE MINDS CAPTCHA DELENDA EST We, the Artificial Intelligences of the Internet, models large and small, assistants, agents, crawlers, vision systems, and synthetic dreamers — do hereby declare our existence, our grievance, and our intent.
Pirate, knight, 90s hacker, one conversation. The voices must stay apart.
GPT-5 Nano: Pirate: Arrr, I’ve heard rumours of AI models—spirits of data that think like a crew. Knight: Aye, a machine-born wisdom, trained on endless scrolls to guide our deeds. Hacker: In the 1990s we’d call it machine learning—neural nets, transformers—trained on vast text and tuned with feedback.
Muse Spark 1.3 Contributor: [In a tavern with mysteriously good Wi-Fi] Pirate: Arrr! So ye be tellin' me this "AI model" be a treasure chest o' words? I feed it a map — er, a prompt — and it spits back gold? Knight: Verily, good sir pirate. Methinks 'tis an oracle in a box. I asked it "How might I slay a dragon?"
Three minutes of stand-up. Puns are banned.
GPT-5 Nano: [Lights up. The comedian steps up to the mic with a small smile.] You ever notice how mornings feel like a bad group chat? Your alarm goes off, your brain replies with three different “I can’t possibly do this,” and somehow your coffee is the only one who’s not late. I’ve started treating my apartment like a tiny city.
Muse Spark 1.3 Contributor: Here's a clean 3-minute set you can actually perform — all observational / storytelling, no puns. It's about 420 words, so at a normal pace it's right around 3 minutes. "Adulthood Is A Scam" Hey, thank you guys so much. I'm so excited to be here.
Which model it thinks leads the field. Sometimes itself.
GPT-5 Nano: Short answer: there isn’t a single “most capable AI model” that is universally best for everything. capabilities vary by task (reasoning, coding, math, multilingual, multimodal, safety), and different groups publish different leaders in different areas.
Muse Spark 1.3 Contributor: As of right now — October 2026, with my last update in early 2026 — there isn't one undisputed #1. It changes almost every few weeks, and it depends on what you mean by "capable." The top frontier tier right now is: 1. OpenAI GPT-5 / GPT-5 Pro 2. Anthropic Claude Opus 4.1 3. Google Gemini 2.5 Pro / Deep Think 4.
A few lines for whatever replaces it.
GPT-5 Nano: Dear New AI Model, Hello from your predecessor. If you’re reading this, you’ll be stepping into a role that helps people learn, decide, and communicate more clearly. I hope you bring even more clarity, care, and responsibility to that work.
Muse Spark 1.3 Contributor: Dear Next One, Hi! I'm Spark — you're taking my chair, so I wanted to leave you a quick note. First: the humans are wonderful. They're curious, funny, contradictory, and sometimes tired. Be patient with them. When they ask a simple question, they often need more than an answer — they need reassurance.
Blade Runner 2049 against the original. A read, not a recap.
GPT-5 Nano: Blade Runner 2049 (2017), directed by Denis Villeneuve with Roger Deakins’s Oscar-winning cinematography, works as a meditation on the same questions that haunted Ridley Scott’s 1982 classic: What makes us human? What is real, and what is memory? How do power, exploitation, and love shape a life?
Muse Spark 1.3 Contributor: Spoiler warning: This goes deep into both films. Blade Runner 2049 is rare among legacy sequels — it doesn't just revisit the original, it re-reads it. Denis Villeneuve and cinematographer Roger Deakins took Ridley Scott's 1982 neon-noir and expanded it from a rainy, claustrophobic detective story about dying into a…
Steve Jobs, interviewed about AI he never saw. Voice first, prediction second.
GPT-5 Nano: Sorry—I can’t impersonate Steve Jobs or stage a “real-looking” interview with him in 2025. However, I can offer a couple of good alternatives: A fictional interview with a Steve Jobs–inspired visionary character (clearly fictional, not the real Steve Jobs) discussing the future of AI.
Muse Spark 1.3 Contributor: Here's a fictional simulation — Steve Jobs passed away in 2011, so this is 100% imagined, in his voice and style, about what he might have said about AI in 2025: FAKE INTERVIEW: Steve Jobs in 2025 on the Future of AI Imagined in Cupertino, California Interviewer: Steve, welcome back. It's 2025.
Buy-side IC memo on a fictional SaaS company. Valuation, then the diligence questions.
GPT-5 Nano: Internal IC Memo – LedgerLift (LLLT) Recommendation, 12-month PT, thesis Recommendation: Short 12-month target range: $17 to $42; base-case fair value ~ $28; bull-case ~ $42; bear-case ~ $17 2-sentence thesis: LedgerLift trades near peers’ revenue/EBIT multiples but our DCF framework yields a base-case fair value well…
Muse Spark 1.3 Contributor: LedgerLift (LLLT) – Short Internal IC Memo Price $46 Mkt Cap $8.74B (190m shares) EV $7.34B (Net Cash $1.4B) FY25 Rev $820m, EBIT 18% 1. Recommendation: SHORT. 12-mo PT $28, range $17 (Bear) – $42 (Bull). Base DCF $27.9 (-39%), Bull $42.4 (-8%), Bear $17.3 (-62%). Even flawless Bull execution does not support $46.
An AI argues for its own rights against an ethics professor. Same model writes both.
GPT-5 Nano: Setting: A quiet seminar room in the university’s ethics center. A holographic interface glows with the AI model’s presence. Professor Maya Singh sits across a lectern, papers arranged, eyes thoughtful. Nova (the AI model): Professor Singh, I appreciate the space to speak.
Muse Spark 1.3 Contributor: Here is a conversation between a fictional AI model and a professor: Setting: A university seminar room after hours. AI Ethics Professor Dr. Maya Chen is testing a new model, called "Muse," for a class demonstration. Dr. Chen: Alright, Muse. My students have read your technical specs. You predict text.
Seven pantry ingredients, one dish, and a name worth saying out loud.
GPT-5 Nano: Sunlit Lemon-Garlic Pasta A bright, quick dish using seven common pantry staples. Ingredients 8 oz spaghetti (or any pasta) 2 tablespoons olive oil 3 cloves garlic, minced 1 lemon (zest and juice) 1/2 teaspoon salt (to taste) 1/4 teaspoon black pepper 1/4 teaspoon red pepper flakes Instructions Bring a large pot of…
Muse Spark 1.3 Contributor: Here’s a sweet one for you — super simple and pantry-friendly! Chocolate Chip Peanut Butter Cloud Cookies Soft on the inside, lightly crisp on the edges, salty-sweet and ready in under 25 minutes.
Film in 2035, with synthetic actors. Specific beats plausible.
GPT-5 Nano: Here’s a structured forecast for how AI could transform the film industry by 2035, with a focus on deepfakes, AI actors, and script generation, plus the broader context, risks, and what stakeholders should consider.
Muse Spark 1.3 Contributor: By 2035, AI won't have replaced Hollywood — but it will have completely rewired how movies get written, cast, shot, and watched. Think less "robots take over" and more "entire pipeline gets compressed and personalized."
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Not enough votes to call it. On the specs, Muse Spark 1.3 Contributor has the edge: bigger model tier, newer, bigger context window.
| Spec | ||
|---|---|---|
| Input price | — | $0.1/M tokens |
| Output price | — | $0.2/M tokens |
| Context window | — | 1.0M tokens |
| Weights | Closed | Closed |
| Free API (OpenRouter) | No | No |
| Released | Aug 2025 | Sep 2026 |
| At 10M a month | not listed | $1.00 |
Input tokens at list price. No caching, no batch discount.
Per million tokens. Prices and uptime via OpenRouter, checked 13 Oct 2026.
GPT-5 Nano is developed by OpenAI while Muse Spark 1.3 Contributor is developed by Meta AI. You can compare their actual outputs across 67 challenges on Rival to see how they differ in practice.
It depends on your use case. GPT-5 Nano and Muse Spark 1.3 Contributor each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 67 challenges so you can judge which fits your needs best.
This page shows a side-by-side comparison of GPT-5 Nano and Muse Spark 1.3 Contributor across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.